keyword
MENU ▼
Read by QxMD icon Read
search

Mutation rate

keyword
https://www.readbyqxmd.com/read/28645195/mutational-biases-influence-parallel-adaptation
#1
Arlin Stoltzfus, David M McCandlish
While mutational biases strongly influence neutral molecular evolution, the role of mutational biases in shaping the course of adaptation is less clear. Here we consider the frequency of transitions relative to transversions among adaptive substitutions. Because mutation rates for transitions are higher than those for transversions, if mutational biases influence the dynamics of adaptation, then transitions should be over-represented among documented adaptive substitutions. To test this hypothesis, we assembled 2 sets of data on putatively adaptive amino acid replacements that have occurred in parallel during evolution, either in nature or in the laboratory...
June 22, 2017: Molecular Biology and Evolution
https://www.readbyqxmd.com/read/28644569/gastrointestinal-stromal-tumors-of-the-esophagus-a-clinicopathologic-and-molecular-analysis-of-27-cases
#2
Guhyun Kang, Yuna Kang, Kyung-Hee Kim, Sang Yun Ha, Jung Yeon Kim, Young Mog Shim, Michael C Heinrich, Kyoung-Mee Kim, Christopher L Corless
AIMS: Gastrointestinal stromal tumors (GISTs) may arise anywhere in the gastrointestinal tract, but are rare in the esophagus. We describe the clinical, pathologic, and molecular characteristics of 27 primary esophageal GISTs, the largest series to date. METHODS AND RESULTS: DNA was extracted and exons 9, 11, 13 and 17 of KIT, exons 12, 14 and 18 of PDGFRA and exon 15 of BRAF were amplified and sequenced. Esophageal GISTs occurred in 14 men and 13 women between 22 and 80 years of age (mean, 56 years)...
June 23, 2017: Histopathology
https://www.readbyqxmd.com/read/28644547/a-genetic-epidemiology-study-of-congenital-adrenal-hyperplasia-in-italy
#3
Alessandro Gialluisi, Soara Menabò, Lilia Baldazzi, Letizia Casula, Antonella Meloni, Maria Carla Farci, Stefano Mariotti, Luisa Balestrino, Rita Ortolano, Stefania Murru, Carlo Carcassi, Sandro Loche, Antonio Balsamo, Giovanni Romeo
Congenital Adrenal Hyperplasia due to 21-hydroxylase deficiency (21OHD-CAH) is an autosomal recessive disorder affecting steroidogenesis, due to mutations in CYP21A2 (6p21.3). 21OHD-CAH neonatal screening is based on 17-hydroxyprogesterone (17OHP) serum levels, showing high type I error rate and low sensitivity to mild CAH forms. Here, we used an epidemiological approach, which estimates the allelic frequency (q) of an autosomal recessive disorder using the proportion of homozygous patients, the mutational spectrum and the inbreeding coefficient in a sample of affected individuals...
June 23, 2017: Clinical Genetics
https://www.readbyqxmd.com/read/28644156/clinical-case-of-the-month-a-57-year-old-man-with-an-axillary-mass
#4
Palak Desai, Andrew Myers, Brian Boulmay, Fred A Lopez
A 57-year-old man presented to the surgical oncology clinic with a mildly tender mass under his right arm. Four years prior, the patient had a melanoma removed from his right shoulder along with an ipsilateral right axillary sentinel lymph sampling. Computed tomography (CT) scan was negative for metastatic disease at that time. The patient did not undergo completion axillary node dissection and was lost to follow-up. The patient was originally from Australia, did not tan but reported multiple sunburns before age 18...
May 2017: Journal of the Louisiana State Medical Society: Official Organ of the Louisiana State Medical Society
https://www.readbyqxmd.com/read/28644114/midostaurin-plus-chemotherapy-for-acute-myeloid-leukemia-with-a-flt3-mutation
#5
Richard M Stone, Sumithra J Mandrekar, Ben L Sanford, Kristina Laumann, Susan Geyer, Clara D Bloomfield, Christian Thiede, Thomas W Prior, Konstanze Döhner, Guido Marcucci, Francesco Lo-Coco, Rebecca B Klisovic, Andrew Wei, Jorge Sierra, Miguel A Sanz, Joseph M Brandwein, Theo de Witte, Dietger Niederwieser, Frederick R Appelbaum, Bruno C Medeiros, Martin S Tallman, Jürgen Krauter, Richard F Schlenk, Arnold Ganser, Hubert Serve, Gerhard Ehninger, Sergio Amadori, Richard A Larson, Hartmut Döhner
Background Patients with acute myeloid leukemia (AML) and a FLT3 mutation have poor outcomes. We conducted a phase 3 trial to determine whether the addition of midostaurin - an oral multitargeted kinase inhibitor that is active in patients with a FLT3 mutation - to standard chemotherapy would prolong overall survival in this population. Methods We screened 3277 patients, 18 to 59 years of age, who had newly diagnosed AML for FLT3 mutations. Patients were randomly assigned to receive standard chemotherapy (induction therapy with daunorubicin and cytarabine and consolidation therapy with high-dose cytarabine) plus either midostaurin or placebo; those who were in remission after consolidation therapy entered a maintenance phase in which they received either midostaurin or placebo...
June 23, 2017: New England Journal of Medicine
https://www.readbyqxmd.com/read/28643785/dnmt3a-mutant-transcript-levels-persist-in-remission-and-do-not-predict-outcome-in-patients-with-acute-myeloid-leukemia
#6
V I Gaidzik, D Weber, P Paschka, A Kaumanns, S Krieger, A Corbacioglu, J Krönke, S Kapp-Schwoerer, D Krämer, H-A Horst, I Schmidt-Wolf, G Held, A Kündgen, M Ringhoffer, K Götze, T Kindler, W Fiedler, M Wattad, R F Schlenk, L Bullinger, V Teleanu, B Schlegelberger, F Thol, M Heuser, A Ganser, H Döhner, K Döhner
We investigated the prognostic impact of minimal residual disease (MRD) monitoring in acute myeloid leukemia (AML) patients harboring DNA methyltransferase 3A-R882H/-R882C mutations (DNMT3A(mut)). MRD was determined by real-time quantitative polymerase chain reaction (RQ-PCR) in 1,494 samples of 181 DNMT3A(mut) patients. At the time of diagnosis, DNMT3A(mut) transcript levels did not correlate with presenting clinical characteristics, concurrent gene mutations as well as the survival endpoints. In Cox regression analyses, bone marrow DNMT3A(mut) transcript levels (log 10 transformed continuous variable) were not associated with the rate of relapse or death...
June 23, 2017: Leukemia: Official Journal of the Leukemia Society of America, Leukemia Research Fund, U.K
https://www.readbyqxmd.com/read/28642787/mutational-signatures-are-critical-for-proper-estimation-of-purifying-selection-pressures-in-cancer-somatic-mutation-data-when-using-the-dn-ds-metric
#7
Jimmy Van den Eynden, Erik Larsson
Large cancer genome sequencing initiatives have led to the identification of cancer driver genes based on signals of positive selection in somatic mutation data. Additionally, the identification of purifying (negative) selection has the potential to identify essential genes that may be of therapeutic interest. The most widely used way of quantifying selection pressures in protein-coding genes is the dN/dS metric, which compares non-synonymous to synonymous substitution rates. In this study, we examine whether and how this metric is influenced by the mutational processes that have been active during tumor evolution...
2017: Frontiers in Genetics
https://www.readbyqxmd.com/read/28642681/%C3%AE-1-containing-gaba-a-receptors-cluster-at-synapses-where-they-mediate-slower-synaptic-currents-than-%C3%AE-2-containing-gaba-a-receptors
#8
Christine L Dixon, Pankaj Sah, Angelo Keramidas, Joseph W Lynch, Nela Durisic
GABA-A receptors (GABAARs) are pentameric ligand-gated ion channels that are assembled mainly from α (α1-6), β (β1-3) and γ (γ1-3) subunits. Although GABAARs containing γ2L subunits mediate most of the inhibitory neurotransmission in the brain, significant expression of γ1 subunits is seen in the amygdala, pallidum and substantia nigra. However, the location and function of γ1-containing GABAARs in these regions remains unclear. In "artificial" synapses, where the subunit composition of postsynaptic receptors is specifically controlled, γ1 incorporation slows the synaptic current decay rate without affecting channel deactivation, suggesting that γ1-containing receptors are not clustered and therefore activated by diffuse neurotransmitter...
2017: Frontiers in Molecular Neuroscience
https://www.readbyqxmd.com/read/28642124/identification-of-genetic-variants-associated-with-huntington-s-disease-progression-a-genome-wide-association-study
#9
Davina J Hensman Moss, Antonio F Pardiñas, Douglas Langbehn, Kitty Lo, Blair R Leavitt, Raymund Roos, Alexandra Durr, Simon Mead, Peter Holmans, Lesley Jones, Sarah J Tabrizi
BACKGROUND: Huntington's disease is caused by a CAG repeat expansion in the huntingtin gene, HTT. Age at onset has been used as a quantitative phenotype in genetic analysis looking for Huntington's disease modifiers, but is hard to define and not always available. Therefore, we aimed to generate a novel measure of disease progression and to identify genetic markers associated with this progression measure. METHODS: We generated a progression score on the basis of principal component analysis of prospectively acquired longitudinal changes in motor, cognitive, and imaging measures in the 218 indivduals in the TRACK-HD cohort of Huntington's disease gene mutation carriers (data collected 2008-11)...
June 19, 2017: Lancet Neurology
https://www.readbyqxmd.com/read/28641695/-relationship-between-egfr-mutations-and-pathological-classification-and-%C3%A2-specimen-of-lung-adenocarcinoma
#10
Lifei Kang, Jie Zheng, Xiang Zhu
BACKGROUND: With the development of genetic mutations and targeted drugs, accurate therapy of lung adenocarcinoma attracts much more attention, and more research is focued on epidermal growth factor receptor (EGFR). It is unclear whether the result of EGFR mutation and pathology type is consistent with different specimens. In our study, by comparing the relationship between EGFR mutations and pathological classification of lung adenocarcinoma in surgical resection of specimen and biopsy specimen, to discuss the relationship between EGFR mutations and pathological classification of and the influence of specimen type on EGFR gene detection...
June 20, 2017: Zhongguo Fei Ai za Zhi, Chinese Journal of Lung Cancer
https://www.readbyqxmd.com/read/28641622/-variation-of-lnk-gene-in-chronic-myeloid-leukemia
#11
Mei Tan, Ying Rong, Run-Mei Tian, Yu-Hang Zhu, Ping Zhu, Yan Chen
OBJECTIVE: To compare the mutation and single nucleotide polymorphism (SNP) of LNK gene between chronic myeloid leukemia(CML) and control groups, and to explore the relationship between LNK gene variation and the occurrence of CML. METHODS: A total of 36 patients with CML were selected, 46 healthy persons were used as normal controls. DNA was extracted from bone marrow and peripheral blood, BCR/ABL1 fusion gene was detected by Q-PCR. The whole exon of LNK gene was amplified by PCR...
June 2017: Zhongguo Shi Yan Xue Ye Xue za Zhi
https://www.readbyqxmd.com/read/28641617/-biological-characteristics-and-therapeutic-efficacy-of-103-patients-with-acute-erythroleukemia
#12
Yue Yin, Wen-Qi Zhan, Hui-Fang Huang, Chen-Qing Zhang, Dang-Hui Fu, Shu-Juan Xu, Jian-Da Hu, Xin-Ji Chen
OBJECTIVE: To investigate the biological characteristics and therapeutic efficacyt of acute erythroleukemia (AEL,AML-M6). METHODS: Blood cell count, liver function, lactate dehydrogenase level, coagulation, morphology, immunology, cell genetics and molecular biology were retrospectively analyzed in 103 cases of acute erythroleukemia patients admitted in our department from May 2016 to June 2009. The therapeutic efficacy was observed by means of remission rate, relapse rate, relapse-free survival and overall survival...
June 2017: Zhongguo Shi Yan Xue Ye Xue za Zhi
https://www.readbyqxmd.com/read/28640841/a-sorghum-sorghum-bicolor-mutant-with-altered-carbon-isotope-ratio
#13
Govinda Rizal, Shanta Karki, Vivek Thakur, Samart Wanchana, Hugo Alonso-Cantabrana, Jacque Dionora, John E Sheehy, Robert Furbank, Susanne von Caemmerer, William Paul Quick
Recent efforts to engineer C4 photosynthetic traits into C3 plants such as rice demand an understanding of the genetic elements that enable C4 plants to outperform C3 plants. As a part of the C4 Rice Consortium's efforts to identify genes needed to support C4 photosynthesis, EMS mutagenized sorghum populations were generated and screened to identify genes that cause a loss of C4 function. Stable carbon isotope ratio (δ13C) of leaf dry matter has been used to distinguishspecies with C3 and C4 photosynthetic pathways...
2017: PloS One
https://www.readbyqxmd.com/read/28640835/bilateral-blockade-of-mek-and-pi3k-mediated-pathways-downstream-of-mutant-kras-as-a-treatment-approach-for-peritoneal-mucinous-malignancies
#14
Murali R Kuracha, Peter Thomas, Brian W Loggie, Venkatesh Govindarajan
Mucinous colorectal adenocarcinomas (MCAs) are clinically and morphologically distinct from nonmucinous colorectal cancers (CRCs), show a distinct spectrum of genetic alterations (higher KRAS mutations, lower p53, high MUC2), exhibit more aggressive behavior (more prone to peritoneal dissemination and lymph node involvement) and are associated with poorer response to chemotherapy with limited treatment options. Here, we report the effectiveness of combinatorial targeting of two KRAS-mediated parallel pathways in reducing MUC2 production and mucinous tumor growth in vitro and in vivo...
2017: PloS One
https://www.readbyqxmd.com/read/28640807/lack-of-a-peroxiredoxin-suppresses-the-lethality-of-cells-devoid-of-electron-donors-by-channelling-electrons-to-oxidized-ribonucleotide-reductase
#15
Susanna Boronat, Alba Domènech, Mercè Carmona, Sarela García-Santamarina, M Carmen Bañó, José Ayté, Elena Hidalgo
The thioredoxin and glutaredoxin pathways are responsible of recycling several enzymes which undergo intramolecular disulfide bond formation as part of their catalytic cycles such as the peroxide scavengers peroxiredoxins or the enzyme ribonucleotide reductase (RNR). RNR, the rate-limiting enzyme of deoxyribonucleotide synthesis, is an essential enzyme relying on these electron flow cascades for recycling. RNR is tightly regulated in a cell cycle-dependent manner at different levels, but little is known about the participation of electron donors in such regulation...
June 22, 2017: PLoS Genetics
https://www.readbyqxmd.com/read/28640323/lys-42-43-44-and-arg-12-of-thrombin-activable-fibrinolysis-inhibitor-comprise-a-thrombomodulin-exosite-essential-for-its-antifibrinolytic-potential
#16
Chengliang Wu, Alan R Stafford, James C Fredenburgh, Jeffrey I Weitz, Ann Gils, Paul J Declerck, Paul Y Kim
The thrombin-thrombomodulin (TM) complex activates thrombin-activable fibrinolysis inhibitor (TAFI) more efficiently than thrombin alone. The exosite on TAFI required for its TM-dependent activation by thrombin has not been identified. Based on previous work by us and others, we generated TAFI variants with one or more of residues Lys 42, Lys 43, Lys 44 and Arg 12 within the activation peptide mutated to alanine. Mutation of one, two, or three Lys residues or the Arg residue alone decreased the catalytic efficiency of TAFI activation by thrombin-TM by 2...
June 22, 2017: Thrombosis and Haemostasis
https://www.readbyqxmd.com/read/28640090/efficiency-of-microarray-and-snpscan-for-the-detection-of-hearing-loss-gene-in-71-cases-with-nonsyndromic-hearing-loss
#17
Rui Han, Linge Li, Ling Duan, Yan Xia, Pilidong Kuyaxi, Juan Zhao, Qi Zhao, Hua Zhang, Yu Chen
We aim to screen the mutations of 3 hearing loss (HL) genes (GJB2, SLC26A4, and 12S rRNA) in 71 cases with nonsyndromic hearing loss (NSHL) using microarray and SNPscan, and identify the roles of nonhotspot mutation of these genes in the screening of NSHL. Seventy-one cases with moderate or severe neurosensory deafness confirmed in our department from July 2014 to December 2015 including 25 Uyghur minorities and 46 Han Chinese were included in this study. The type of mutations in GJB2, SLC26A4, and 12S rRNA genes were detected using microarray and SNPscan, respectively...
June 2017: Medicine (Baltimore)
https://www.readbyqxmd.com/read/28639892/jak2-variations-and-functions-in-lung-adenocarcinoma
#18
Yanjun Xu, Juan Jin, Jiawei Xu, Yang W Shao, Yun Fan
Lung cancer ranks as the first most common cancer and the first leading cause of cancer-related death in China and worldwide. Due to the difficulty in early diagnosis and the onset of cancer metastasis, the 5-year survival rate of lung cancer remains low. JAK2 has emerged as pivotal participant in biological processes, often dysregulated in a range of cancers. Recently our study found that JAK2 might play an important role in lung cancer pathogenesis. While our understanding of JAK2 in the onset and progression of lung cancer is still in its infancy, there is no doubt that understanding the variations and functions of JAK2 will certainly secure strong biomarkers and improve treatment options for lung cancer patients...
June 2017: Tumour Biology: the Journal of the International Society for Oncodevelopmental Biology and Medicine
https://www.readbyqxmd.com/read/28639657/exploring-the-catalytic-mechanism-of-dihydropteroate-synthase-elucidating-the-differences-between-the-substrate-and-inhibitor
#19
Warot Chotpatiwetchkul, Kanokthip Boonyarattanakalin, Duangkamol Gleeson, M Paul Gleeson
Dihydropteroate synthase (DHPS) catalyzes the condensation of 6-hydroxymethyl-7,8-dihydropterin pyrophosphate (DHPPP) with p-aminobenzoic acid (pABA) and is a well validated target for anti-malarial and anti-bacterial drugs. However, in recent years its utility as a therapeutic target has diminished considerably due to multiple mutations. As such, considerable structural biology and medicinal chemistry effort has been expended to understand and overcome this issue. To date no detailed computational analysis of the protein mechanism has been made despite the detailed crystal structures and multiple mechanistic proposals being made...
June 22, 2017: Organic & Biomolecular Chemistry
https://www.readbyqxmd.com/read/28639151/central-arterial-function-measured-by-non-invasive-pulse-wave-analysis-is-abnormal-in-patients-with-duchenne-muscular-dystrophy
#20
Thomas D Ryan, John J Parent, Zhiqian Gao, Philip R Khoury, Elizabeth Dupont, Jennifer N Smith, Brenda Wong, Elaine M Urbina, John L Jefferies
Duchenne muscular dystrophy (DMD) is an X-linked recessive disorder caused by mutation of dystrophin. Cardiovascular involvement includes dilated cardiomyopathy. Non-invasive assessment of vascular function has not been evaluated in DMD. We hypothesize arterial wave reflection is abnormal in patients with DMD. Pulse wave analysis was performed on DMD patients with a SphygmoCor SCOR-PVx System to determine central blood pressure and augmentation index (AIx) as an assessment of arterial wave reflection. Results were compared to a control group...
June 21, 2017: Pediatric Cardiology
keyword
keyword
50121
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"